The Internet has enabled computer users all over the world to interact and communicate electronically. One particularly popular mode for communication features Web pages, which collectively form the World Wide Web. Web pages are useful for displaying text and graphics, and even animation, video data and audio data. However, the explosion of information has made it more difficult for users to find the information of interest.
Various generic search engines are available which attempt to provide such information to users. For example, Google®, Yahoo®, Ask®, Bing® (Microsoft) are all examples of search engines which can be used by any user to search any topic. However, their generic nature also renders them non-specific; for example, certain types of specialized searches simply cannot be performed through these search engines (AKA the deep web).